Reagent feeder



J. S. WATTS REAGENT FEEDER Aug. 30, 1938.

Filed 001;. 19, 1,935

INVENTOR. 77m '2 ATTORNEYS.

BY MK Patented Aug. 30, 1938 UNETE S'i' i orrics 4 Claims.

This invention relates to reagent feeders and.

more particularly to a device for the treatment of Water in the pipes of buildings with anti-corrosive reagents. Corrosion and consequent rusty water can be eliminated from the water system of any building b-ythe use of silicate of soda, providing the silicate is added in. proper proportion to the amount of water used, although the amount of silicate may Vary throughout a fairly wide range. V

An object of this invention is a reagent feeder of simple construction and low cost which operates efilciently to introduce a reagent such as silicate of soda into the water system of a,

building.

A reagent feeder embodying the invention is operated by variations in the water pressure in the system. When there is no flow through the water system of a building, the pressure is static but when there is a flow, there is a consequent fall of pressure, the extent of which is a function of the quantity of flow. During constant flow, there is a fluctuation of pressure due to hunting for a balance between pressure drop, pipe friction and the inertia of the water. As a result, there are caused waves of pressure having an intensity and periodicity the total effect of which is proportional to the consumption of water. In the present invention, these pressure fluctuations are 30 utilized to pump reagent into the water of the system. The reagent is thus introduced intermittently, in small amounts and is so distributed throughout the system as to function effectively to prevent corrosion of the pipes of the system.

Other objects, novel features and advantages of this invention will become apparent from the following specification and accompanying drawing, wherein:

Fig. 1 illustrates one embodiment of the inven- 40 tion, and

Fig. 2 illustrates a modified form of the invention.

In Fig. 1, l0 designates a main comprising part of a water system for a building connected to a source of water at substantially constant static pressure. A pipe ll provided with a valve l2 leads from the main it] to the head ltd of the cylinder l3. In the other head i312 of the cylinder is provided a reciprocating pump it, the plunger l5 of which is connected to a piston 85 slidably mounted in the cylinder i3. A pipe I! leads from a tank Hi to the inlet of the pump M to the main H). An air chamber 20 communicates with the interior of the cylinder l3 through the head iiib The water pressure applied to the left side of the piston H5 is balanced by the pressure of the air trapped in the dome 20 and when no water is flowing in the main in, the piston l6 remains stationary. However, upon flow in the main [0, the pressure applied to the left side of the piston it drops with the result that the air in the vessel 8!] expands, thereby pushing the piston It to the leftuntil the pressure on opposite sides of the piston is again equalized. This movement to the left of the piston thus gives a suction stroke to the plunger l5, thereby drawing in liquid from the tank 58. Upon cessation of flow in the main it, the water pressure on the left side of the piston It returns to its original strength, thereby forcing the piston I3 to the right until there is equalization of pressure on both sides of the piston. The accompanying movement of the plunger 15 to the right discharges liquid through the outlet of the pump by way of the pipe l9 into the main it. Thus, every time that a faucet 9 of the water system is opened and closed, a certain amount of reagent is added to the water in the main !0. There is no definite ratio between the amount of added liquid and the quantity of water drawn off, but each time there is any flow there is addition of reagent, the reagent being added after cessation of flow so that it is not immediately carried out of the system. This gives the reagent a chance to disseminate throughout the water while the latter is quiescent and with proper adjustment of the valve I2 after observation of the ordinary use made of the water system, proper proportioning can be made so that sufficient reagent will be added to prevent corrosion without substantial waste of reagent.

In the modification disclosed in Fig. 2, a spring is utilized to counterbalance the water pressure. Otherwise, the embodiment of Fig. 2 operates on the same principle as the embodiment of Fig. 1.

The cylinder is is provided with a head [3a. and

a head 53b in the latter of which is mounted the pump M having its inlet connected by pipe I! to the reagent tank 18 and its outlet connected by pipe 99 with the water main Ill. A pipe II leads from. the water main l0 through a duct 2| in the cylinder l3 to the left end of the cylinder so that the water pressure is applied to the left face of the piston I6. A cross-bar 22 surrounds the pump plunger l 5 in engagement with a shoulder on the piston l6 and projects through slots in the cylinder I 3, its ends being connected to one end of the spring 23. The other end of the spring 23 is supported by hand wheel 2% threaded on a rod 25 carried by the head 53a. The tension of the spring 23 may be varied by rotation of the hand wheel 26 to move it on the rod 25.

In this modification, the Water pressure applied to the left face of the piston l 6 is balanced by the spring 23. If there is flow in the pipe H3, with consequent decrease of pressure applied to the left face of the piston 86, the latter moves to the left under the influence of the spring 23 until there is equalization of pressure. There is corresponding movement of the pump plunger M to the left, thus drawing in reagent from the tank l8 and upon cessation of flow in the main Hi, the piston l5 and plunger l5 are moved to the right, thereby forcing the reagent into the pipe iii.

In both modifications, there is some pumping action even with constant flow as there is a fluctuation of pressure in the main due to a variety of causes. Such pressure fluctuation will produce slight vibratory movement of the plunger l5 with consequent pumping of reagent. The main addition of reagent is effected, however, upon cessation of water flow as at that time the piston makes a full stroke back to its original position. The amount of reagent added to the Water is .determined by the Water consumption and over a given period will in general bear a substantially uniform ratio to the amount of Water used.

It is to be understood that the invention is not limited to devices for adding anti-corrosive reagent to water systems but that it has been described in such connection merely as an example of its use. Furthermore, it is to be understood that various modifications may be made in the structure of the devices above described, without in any Way departing from the spirit of the invention as defined in the appended claims.

In the embodiment disclosed in Fig. 1, the rate of feed of reagent may be varied by adjustment of the valve l2 thereby damping the pressure fluctuations and reducing their eiTect on the piston with consequent shortening of the strokes of the plunger. Once adjusted for the desired ratio of reagent, the device will repeat the ratio indefinitely.

I claim:

1. 'In a water supply system having a source of water at substantially constant static pressure, a main in communication with said source of water, and valve means operable to cause flow of water through said main, that improvement which comprises a source of liquid reagent, means including a pump for feeding said reagent to said main, and means responsive solely to pressure decrease in said main resulting from water flow and return to normal pressure upon cessation of water flow for controlling the operation of said pump to force liquid reagent into said main upon substantial cessation of water flow.

2. In combination, a source of liquid at substantially constant static pressure, a main in communication with said source of liquid, valve means operable to cause flow of liquid through said main, a liquid reagent source, a vibratory member, means for continuously applying the liquid pressure in said main to one side of said member, means for applying counterbalancing pressure to the other side of said member, and means including a pump actuated by said member for feeding said reagent to said main, said member being operated solely upon decrease in pressure in the main resulting from liquid flow and return to normal pressure upon cessation of flow for actuating said pump to force liquid reagent into said main upon substantial cessation of liquid flow.

3. In combination, a source of liquid at substantially constant static pressure, a main in communication with said source of liquid, valve means operable to cause flow of liquid through said main, a liquid reagent source, a vibratory member, means for continuously applying the liquid pressure in said main to one side of said member, an air dome for applying counterbalancing pressure to the other side of said member, and means including a pump actuated by said member for feeding said reagent to said main, said member being operated solely upon decrease in pressure in the main resulting from liquid flow and return to normal pressure upon cessation of flow for actuating said pump to force liquid reagent into said main upon substantial cessation of liquid flow.

4. In combination, a source of liquid at substantially constant static pressure, a main in communication with said source of liquid, valve means operable to cause flow of liquid through said main, a liquid reagent source, a vibratory member, means for continuously applying the liquid pressure in said main to one side of said member, a spring connected to said member to counterbalance said liquid pressure, and means including a pump actuated by said member for feeding said reagent to said main, said member being operated solely upon decrease in pressure in the main resulting from liquid flow and return to normal pressure upon cessation of flow for actuating said pump to force liquid reagent into said main upon substantial cessation of liquid flow.

JOHN S. WATTS. 

